Ex. 4.2
 THIS WARRANT AND THE SECURITIES REPRESENTED BY THIS WARRANT HAVE NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933 OR THE SECURITIES ACT OF ANY STATE AND
MAY NOT BE SOLD OR TRANSFERRED UNLESS THERE IS AN EFFECTIVE REGISTRATION STATEMENT
UNDER SUCH ACTS COVERING THIS WARRANT AND THE SECURITIES REPRESENTED BY THIS
WARRANT OR PURSUANT TO AN EXEMPTION FROM THE REGISTRATION AND PROSPECTUS DELIVERY
REQUIREMENTS OF SUCH ACTS.
 BIOLARGO, INC.
 FORM OF WARRANT TO PURCHASE COMMON STOCK
(One-Year Warrant)
 WARRANT NO.W-XXX
    
    ISSUED:XXXX, 2009
 XXXX Holder Company XXXX Shares Common
Stock Warrant
Price Section 4
  Method of Exercise; Payment; Issuance of New Warrant
 Exhibit A Exhibit A




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Stock Fully Paid; Reservation of Shares
 Fractional Shares
 Adjustment
 Adjustment for Stock Splits and Combinations
 Adjustment for Certain Dividends and Distributions
 (x)
    
    the numerator of which shall be the total number of shares of Common
Stock issued and outstanding immediately prior to the time of such
issuance; and
 (y)
    
    the denominator of which shall be the total number of shares of Common
Stock issued and outstanding immediately prior to the time of such
issuance plus the number of shares of Common Stock issuable in payment of
such dividend or distribution.
  - 2 -




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Adjustment of Number of Shares Section 4(a) 4(b)
 Adjustment for Reclassification, Exchange and Substitution Section 4(a) Section 4(b) Section 4(e)
 Reorganization, Mergers, Consolidations or Sales of Assets Section 4(a) Section 4(b) Section
4(d) Section 4(e)
 No Impairment
 Notice of Adjustments Section 4
  - 3 -




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The Companys Obligation to Make Payments
 Dividends and Distributions Section 4
 Redemption of Capital Stock
 Notice of Record Date
 (1)
    
    that the Company declares a dividend (or any other distribution) on any of its
capital stock (including without limitation, its Common Stock);
 (2)
    
    that the Company repurchases or redeems any of its capital stock (including
without limitation, its Common Stock) or any rights to acquire such capital stock;
 (3)
    
    that the Company subdivides or combines its outstanding shares of Common Stock;
 (4)
    
    of any reclassification of the Common Stock, or of any consolidation, merger or
share exchange of the Company into or with another entity, or of the sale of all or
substantially all of the assets of the Company;
 (5)
    
    of the involuntary or voluntary dissolution, liquidation or winding up of the
Company; or
 (6)
    
    of any offer of its Common Stock or any rights to acquire such Common Stock for
consideration paid per share of Common Stock less than the Warrant Price then in
effect.
  - 4 -




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Compliance with Securities Act; Disposition of Warrant or Common
Stock
 Compliance with Securities Act Act
  Disposition of Warrant or Shares Exhibit B.
 Rights as Shareholders
 Representations and Warranties
   - 5 -




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Modification and Waiver
 Notices
 Descriptive Headings
 Governing Law
 Binding Effect on Successors
 Severability
  - 6 -




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Lost Warrants or Stock Certificates
  BIOLARGO, INC.By:
    
    XXXXXXName:
    

    Dennis P. Calvert, PresidentAddress:
    

    2603 Main Street, Suite 1155
Irvine, California 92614 Attention: Dennis P. Calvert
 ACKNOWLEDGED AND ACCEPTED:By:Print Name:Address:
 
  - 7 -




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EXHIBIT A
 NOTICE OF EXERCISE
  
   (Name)
 (Name)
  (Name)
 (Address)
 (Federal ID or Social Security No.)
 (Signature)
 (Date)




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EXHIBIT B
 NOTICE
OF TRANSFER
  
 The undersigned understands that any transfer of the attached Warrant is subject to full
compliance with Federal and applicable state securities laws and other requirements, which
requirements shall be determined and which issues shall be decided by BIOLARGO, INC., in its sole
and absolute discretion, prior to consenting to and recognizing such transfer.
 
 (Signature must conform in all respects to the name of
the Holder as specified on the face of the Warrant)(Address)